Synthetics
The 3dMark scores look fairly indicative of the difference in gaming, even if they are exaggerated.
The Specviewperf benchmark looks like it has mix of CPU and GPU intensive apps. Some show large increases in performance (probably CPU bound) while others show very little increase (probably GPU bound).
Here we see massive gains in the system, CPU, and memory benchmarks reflect our 75% overclock. The hard disk benchmark changes very little, which is to be expected.